re PR c++/53159 (Missing narrowing check)

/cp
2014-07-11  Paolo Carlini  <paolo.carlini@oracle.com>

	PR c++/53159
	* call.c (build_user_type_conversion_1): Copy LOOKUP_NO_NARROWING
	into convflags.
	* decl.c (check_initializer): Don't call check_narrowing here,
	set LOOKUP_NO_NARROWING.
	* typeck2.c (digest_init_r): Likewise.

/testsuite
2014-07-11  Paolo Carlini  <paolo.carlini@oracle.com>

	PR c++/53159
	* g++.dg/cpp0x/Wnarrowing1.C: New.

From-SVN: r212469

gcc/cp/ChangeLog

+2014-07-11  Paolo Carlini  <paolo.carlini@oracle.com>
+
+	PR c++/53159
+	* call.c (build_user_type_conversion_1): Copy LOOKUP_NO_NARROWING
+	into convflags.
+	* decl.c (check_initializer): Don't call check_narrowing here,
+	set LOOKUP_NO_NARROWING.
+	* typeck2.c (digest_init_r): Likewise.
+
 2014-07-10  Jason Merrill  <jason@redhat.com>
 
 	PR c++/61661

gcc/cp/call.c

@@ -3586,7 +3586,8 @@ build_user_type_conversion_1 (tree totype, tree expr, int flags,
 
   /* It's OK to bind a temporary for converting constructor arguments, but
      not in converting the return value of a conversion operator.  */
-  convflags = ((flags & LOOKUP_NO_TEMP_BIND) | LOOKUP_NO_CONVERSION);
+  convflags = ((flags & LOOKUP_NO_TEMP_BIND) | LOOKUP_NO_CONVERSION
+	       | (flags & LOOKUP_NO_NARROWING));
   flags &= ~LOOKUP_NO_TEMP_BIND;
 
   if (ctors)

gcc/cp/decl.c

@@ -5756,8 +5756,7 @@ check_initializer (tree decl, tree init, int flags, vec<tree, va_gc> **cleanups)
 	  else
 	    {
 	      init = reshape_init (type, init, tf_warning_or_error);
-	      if (SCALAR_TYPE_P (type))
-		check_narrowing (type, init);
+	      flags |= LOOKUP_NO_NARROWING;
 	    }
 	}
       else if (TREE_CODE (init) == TREE_LIST

gcc/cp/typeck2.c

@@ -1027,7 +1027,7 @@ digest_init_r (tree type, tree init, bool nested, int flags,
       tree *exp;
 
       if (nested)
-	check_narrowing (type, init);
+	flags |= LOOKUP_NO_NARROWING;
       init = convert_for_initialization (0, type, init, flags,
 					 ICR_INIT, NULL_TREE, 0,
 					 complain);

gcc/testsuite/ChangeLog

+2014-07-11  Paolo Carlini  <paolo.carlini@oracle.com>
+
+	PR c++/53159
+	* g++.dg/cpp0x/Wnarrowing1.C: New.
+
 2014-07-11  Andreas Schwab  <schwab@linux-m68k.org>
 
 	PR preprocessor/61389

gcc/testsuite/g++.dg/cpp0x/Wnarrowing1.C

+// PR c++/53159
+// { dg-do compile { target c++11 } }
+// { dg-options "-Wnarrowing -Wno-overflow" }
+
+struct X
+{
+  constexpr operator int() { return __INT_MAX__; }
+};
+
+int f() { return __INT_MAX__; }
+
+signed char a { __INT_MAX__ };     // { dg-warning "narrowing conversion" }
+signed char b { f() };             // { dg-warning "narrowing conversion" }
+signed char c { X{} };             // { dg-warning "narrowing conversion" }
+
+signed char ar[] { __INT_MAX__ };  // { dg-warning "narrowing conversion" }
+signed char br[] { f() };          // { dg-warning "narrowing conversion" }
+signed char cr[] { X{} };          // { dg-warning "narrowing conversion" }